/*
 * Copyright 2017-2020 The OpenTracing Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */
package io.opentracing.contrib.kafka;


import io.opentracing.propagation.TextMap;
import java.nio.charset.StandardCharsets;
import java.util.Iterator;
import java.util.Map.Entry;
import org.apache.kafka.common.header.Headers;

public class HeadersMapInjectAdapter implements TextMap {

  private final Headers headers;

  public HeadersMapInjectAdapter(Headers headers) {
    this.headers = headers;
  }

  @Override
  public Iterator<Entry<String, String>> iterator() {
    throw new UnsupportedOperationException("iterator should never be used with Tracer.inject()");
  }

  @Override
  public void put(String key, String value) {
    headers.add(key, value.getBytes(StandardCharsets.UTF_8));
  }
}
